E-Cigarettes and Vaporizers: A Safe Substitute for Smokers?

Electronic nicotine delivery systems (ENDS) are devices that contain liquid nicotine. Their usage has surged since e-cigarettes (the most popular version) were introduced in the US market in 2007. Many are excited that they may be a safer alternative to cigarette smoking with fewer obnoxious effects on those surrounding the smoker. While the news is exciting, these devices are still fairly new and not fully tested. It is important for medical and safety community to confirm that these devices are safe for the user and those around them. This will take some time and research.

What Devices are Available?

ENDS are battery-powered devices that are available in a range of sizes and shapes. Some look just like real cigarettes, while other e-cigarettes, called vaporizers or vape pens, are designed to look more like pens. Other versions include e-pipes and e-cigars, which are designed to look like the real thing. Although this article focuses on the use of e-cigarettes, the concepts are similar for any ENDS device.

In general, the devices are made up of:

  • A mouthpiece
  • A replaceable (or refillable) cartridge that contains a liquid solution of different strengths of nicotine, flavoring, water, and chemicals.
  • An atomizer, which transforms the liquid solution into a vapor.
  • A rechargeable battery or USB charger. Depending on the style, the battery end of the cigarette may have an LED light on the tip to look like the burning ember on a real cigarette. However, the LED light does not get hot, so it does not pose a fire hazard.

When the user inhales on the mouthpiece, this triggers the liquid to be heated, and the atomizer turns the liquid into a vapor. This vapor is then inhaled by the user, which feels like smoking a real cigarette. When the user exhales, the vapor quickly disappears. Vaporizers produce more clouds of vapor than e-cigarettes.

It is important to understand that these devices are an alternative for those who are already smoking. They should not be used by people who do not already smoke. Adolescents, young adults, and pregnant women should not use these devices.

What Is the Controversy Surrounding these Devices?

There are many e-cigarette brands available to consumers—each with different combinations of nicotine and other chemicals. This variability causes controversy on how e-cigarettes should be regulated, if at all. Regulators, both in and out of the US markets, are looking at e-cigarettes' potential benefits and harms.

Potential Benefits

The most obvious benefit to e-cigarettes is that it may help smokers stop smoking real cigarettes. It is unique to all other current cessation programs because it allows people to continue smoking without inhaling thousands of harmful chemicals normally found in one burning cigarette. But, do e-cigarettes really help smokers quit?

In one controlled trial, a group of 300 smokers were split into 3 groups who received cartridges with either all the same amount of nicotine, a step-down amount of nicotine, or no nicotine. Half the smokers in each group had made past attempts to quit. The median daily smoked cigarettes was about 20 for each group. After 12 weeks, over 20% smoked less cigarettes per day from their baseline amount. Cessation was maintained by over 10% at a 1-year follow-up. Nicotine content seemed to have no effect on the cessation rate among the groups. However, smokers did report big declines in smoking's side effects, such as dry cough, mouth and throat irritation, shortness of breath, and headache.

In 2014, a study with 949 current smokers was published. Participants used e-cigarettes for one year. The study found that using e-cigarettes did not help smokers quit or reduce cigarette consumption. Conversely, a review of 2 other studies showed the 6-month quit rate for e-cigarettes was higher than a non-nicotine placebo. In one of the studies, e-cigarettes were as effective as nicotine patches after 6 months. Though these studies are promising, more research needs to be done before they replace other nicotine replacement therapies.

Currently, the US Food & Drug Administration (FDA), along with several major anti-smoking organizations, have determined that there has not been enough research on e-cigarettes to make any claims about their safety or effectiveness in helping people quit smoking.

Potential Harms

In 2019, US Centers for Disease Control (CDC) released an investigation notice about a possible link between a severe lung illness and e-cigarettes. The cause of severe lung symptoms is not clear. However, an infection had been ruled out as the cause of the problems and all patients affected reported using e-cigarettes. Many reported using cannabinoid products like THC with their device. More research will be done to confirm if there is a link and if so, what part of e-cigarette device or products could be causing the problem.

In the US, regulation for e-cigarettes falls on the FDA's doorstep. New regulations help the FDA gain control of each step in the ENDS process from manufacturing to distribution. These changes are slowly addressing the issues the FDA has faced since these products have hit the market. Products marketed with the intent to help people quit will fall into another category. Changes will take effect in steps through 2019, including nicotine warning statements on packaging.

The concerns among agencies that are driving changes include:

  • Safety and effectiveness of e-cigarettes if used to quit smoking.
  • Wide variation of the amount of nicotine in each e-cigarette.
  • Rising use of e-cigarettes among adolescents.
  • Long-term effects of using e-cigarettes if the intent is not to quit.
  • Safety of liquid nicotine, especially to children.

One of the bigger issues agencies is the chemical make-up of the inhaled vapors. The agency analyzed different e-cigarette brands. They found diethylene glycol (a chemical used in antifreeze) and other cancer-causing agents in some of the samples. The agency is also concerned that the cartridges are not consistent in the amount of nicotine they provide. For example, you may use a low-strength nicotine cartridge, but actually receive a higher dose (or vice versa).

Another issue is the chemical make-up of exhaled vapors. Like cigarette smoke, not all of the chemicals in e-cigarettes remain in the lungs of the smoker. Some of these elements are exhaled into the air where others can breathe in these chemicals. The particles can also land on surfaces, like clothes, furniture, and carpets. Studies on these effects will need to be taken into account during the regulatory process. E-cigarettes are also not included in current public smoking bans, which is causing some states to scramble to put e-cigarettes in the same class as tobacco products, but it may not be that easy.

In recent surveys, perception exists that e-cigarettes are safer and can be used as a tool to stop smoking, especially among adolescent and young adult smokers. Currently, there is too much conflicting information among agencies and manufacturers to make such a broad statement. The bottom line is that e-cigarette users still inhale nicotine and other potentially-hazardous chemicals, but the types and amounts of these chemicals are varied and usually unknown. That's where regulation may help.

Making an Informed Decision

If you are thinking about kicking the habit, your best option would be to weigh out all your options. Some smoking cessation strategies, like nicotine replacement products, prescription medications, organized programs, and support groups, have a proven track record. If you are considering e-cigarettes, discuss the pros and cons with your doctor. It may also make a difference if you are using this as a tool to quit, or a potentially safer substitute for smoking that you plan to continue indefinitely. Making an informed decision is an important step in taking control of your health.


US Food & Drug Administration


Canadian Lung Association


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Last reviewed April 2017 by Michael Woods, MD, FAAP
Last Updated 9/6/2019

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